Lubricating mechanism for strip casting machines



Feb. 6, 1951 H. l.. HORN 2,540,523

LUBRICATING MECHANISM FOR STRIP CASTING MACHINES Filed June 5, 1948HARRY L.. HORN l/ A 1N V EN TOR.

ATTO/ENQ atented 6, 159541 Nmirri) STATES nUBRIoATING MEoHANrsM Fonnsrnljr CASTING MACHINES Harry Horn, Dallas, Ten Application June 5,194s, 'seramo- 315285 1 n This invention relates to new and useful im.provements in lubricating mechanisms for use instrip casting machinesfor making printers leads, slugs and rules.

The machines used for diefexpressing or draws ing strips of type metal'are adapted to form a continuous metal bar by drawing the same fromabody of molten metal, the metal being drawn through the shaped channelof a suitable mold or die and cooled .while passing through saidchannel, so that the metal enters one end of the channel as a fluidandemerges from theother end thereof as a solid strip bar. The movementof the strip or vbar through the channel is effected by pulling ulponthe solidified portion thereof pro,- truding from the die, the moltenmetal being subjected merely to suflicient pressure to `cause it tofollow through the die channel rather than to apressure great enough .todirectly expel or extrude the metal through such channel.

f The lubricating device of the invention is designated particularly forintroducing a lubri.-

cant into the channel of the .die for facilitating the :drawing of theformed metal through the die and preventing frictional adherence of theformed strip to the walls of .the die channel, so thatthe strip isformed with smooth surfaces and of a uniform size.

Qne object of the invention is to provide an improved lubricatingmechanism for inserting lubricant into the ,strip forming channel yofthe dieci a machine for making gprinters leads, Slugsand rules, andthelike.

An important object of the invention is to provide a lubricatingmechanism Ahaving valve means for controlling `the admission oflubricant to the channel of the die of the strip forming machine, saidvalvemeans being normally closed and opened at predetermined intervalsto admit lubricant to Ythe channel 4as aforesaid.

Another .Object of the invention is to provide a lubricating mechanismof the characterde,4 scribed having means for preventing backflow oflubricant or molten `metal into the body of the lubricator mechanism.

.1' A 'particular object nf `the inventionis .to provide a lubricatingapparatus having a reservoir and valve means normally closed andintermittcntlv opened for controlling Ow cf lubricant f said reservoir,the outlet from ythe 'resers voir past the valve means comrnunicatingAwith omal Secondary lubricant chamber having an outlet into the moltenmetal passage ofthe str-ip casting machine, whereby lubricant, fromthe'v reservoir is .admitted at predetermined intervals aolaims, (o1..2a-57.2)

into the-'secondary chamber and is withdrawnfrom said chamber Ainto themolten metal pas-- sage 'of tlliestrip 'casting machine, the secondary'chamber being provided with a backilow ehecl valve at its outlet end forpreventing molten metal'from, entering said chamber.

Another objectief 'the invention is to provide a-flubricatingmechanismof thecharacter dei scribed having. an -improvedactuatingineoha-` nismY for 'opening thev control valve between the lubricant,reservoir `'and theY secondary lubricant' chamber-whereby the Vvalve isopened Yat prede-' termined intervals and vis positively resilientlymaintained closed at-all other times to prevent: undesired flow of oilfrom the-reservoir, .and also to prevent admission of molten metal tosuch reservoir. v ,1 IA still further object of the invention is to)provide :means for adjustably controlling the Imovement ,of `the vvalveseparating the lubricant reservoirfrom the secondary lubricant chambervtocontrol the amountof lubricant `permitted to pass through thevalveYWhen the valve is opened.

Another object of `theinvention is to provide an lubricating system'ofthe character described which lis readily removable and replaceable, ifdesired or necessary.

Additional objects and advantages of the invention .will readily beapparent from the read-- ing of the following description of a deviceconstructed accordance with the invention, and reference to theaccompanying drawingsthereof, Wherein: l

Figure 1 is a view, .partly in elevation and' partly in section, of aportion of a machine formaking .pri-liters leads, slugs, rules, andthezlike, and showing a .lubricating mechanism con;- structed inaccordance with the invention inf" corporated therein,

Figure 2 .isr an enlarged vertical cross-sectional view of thelubricating mechanism, showing the' lubricant admitting val-ve opened topermit pas# sageof oil, and f Figure 3 is a similar view of the valvemecha-* nism, takenatright angles to Figure 2, showingl the lubricantcontrolling valve closed.

-Iii-Itho drawings, the numeral lll designates a melting pot orcrucible, substantially cylindrical inform, which is mounted on a benchor table top .Il of a strin casting machine used for forming continuousbarsof metal from a molten body.

thereof, inthe form of prin-ters? leads, slugs, rules, and the like.Beneath lthe crucible is mounted a:

gas burneror'other lheating' element l2 to which" fuel is supplied'forheating thecru'cible for melt-A` ing the type metal, lead, or similarsoft metal alloys capable of fusion or melting at moderate temperaturesand having a fair degree of tensile strength when cold, which metals areused in forming the strip. The crucible is provided with an outletpassage or spout I3 communicating with the lower portion of the crucibleand extending laterally therefrom. The inner end of the passagecommunicates with the lower end of a pump cylinder I4, which is disposedin the body of the crucible and forms an integral part of the lowerportion or bottom thereof. A piston or plunger I5 is slidable within thecylinder and is actuated by means of a connecting rod I6 extendingupwardly from the piston and connected to one end of a lever I'I whichis fulcrumed between lugs I8 formed on the upper end of the cruciblebody. The lever II is actuated by means of a push rod I9, which isconnected with the outer end thereof and extends downwardly below thetable top to a suitable crank or cam mechanism I9a which causesreciprocating movement of the push rod and thus, likewise, causesreciprocating movement of the piston I5 in the cylinder i4. Suchreciprocating movement of the piston lifts the piston until it ispositioned above a lateral opening 20 in the side wall of the cylinder,whereby molten metal may enter through said opening into the bore of thecylinder, whereupon downward movement of the piston will force the metaloutwardly along the passage of the spout I3 in the usual manner.

A rotatable ported cylindrical plug valve 2I is mounted in the spoutpassage I3 for controlling iiow of molten metal through the passage ofsaid spout. A valve stem 22 extends upwardly from the valve plug to apoint above the upper end of the crucible and is provided with a handle23 for manipulation by the user of the device.

A nozzle or tip member 29 is screw-threaded into the outer end of theoutlet spout or throat I3 from the Crucible and has an axial flowpassage therethrough for permitting the molten metal to flow outwardthrough the nozzle and into the bore or shaped channel of a die or mold3l which determines the form of the strip of type metal produced by themachine. The extreme outer portion or tip of the nozzle is preferablysubstantially hemispherical in configuration, and this hemispherical tipend of the nozzle engages in a concave or frusto-conical opening formedin the entrant end of the die or mold. The details of structure of thedie or mold and the cooling system therefor are not essential to thisinvention, and may comprise any suitable arrangement, though thestructure of the die and cooling system shown and described in myco-pending application for United States Letters Patent, Serial No.20,855, filed April 14, 1948, is preferable. A clutch and pullingmechanism (not shown) of any desired suitable type, is mounted on thetable top I I near the exit end of the die for positively drawing thestrip T of type metal from the die in the usual manner. The strip sodrawn from the die may subsequently be cut into sections of anypredetermined desired length by a cutting mechanism (not shown) of anysuitable or usual structure.

In the forming of the strip of type metal, the metal supplied to the dieenters the bore or channel of the die in molten form and is caused tosolidify or set adjacent the outlet or exit end of the die channel, suchsolidification or setting being eiected by cooling means 30 inheat-exchanging relationship with the die. Since the formed strip mustbe pulled from the exit end of the channel through the die, it becomesreadily apparent that the presence of lubricant in the channel of thedie is desirable for facilitating the passage of the solidified typemetal through the die. The drawing of the formed metal strip from thedie may thus be facilitated by introducing a suitable lubricant, such asengine oil or the like, into the spout, I3 so that portions of thelubricant will be carried into the die channel along with the moltenmetal from the spout passage. It is also important to note that thequantity of lubricantl admitted to the die must be very accuratelycontrolled in accordance with the amounts required for properlylubricating strips of various thicknesses, etc.

For so supplying lubricant, the lubricating mechanism L has beenprovided. The lubricating mechanism includes a cup or container 40having an elongate cylindrical tube or conductor 4I extending axiallydownward from its lower end and containing a flow passage 42. Theportion of the tube adjacent to the bottom ofthe cup is enlarged indiameter and provided with external screw-threads 43, whereby the tubemay be inserted into and secured in an opening 44 in the housing 45 forthe outlet throat from the crucible and extend downwardly therein. A capor cover plate 46 is removably positioned on the upper end of the cup 40and held in place thereon by means of screws 41.

A valve body or housing 59 is screw-threaded onto the lower end of thetube 4I and forms a downward continuation of said tube, the lower` endof said valve body terminating in the throat passage I3 from thecrucible to the outlet nozzle 29. The valve body is provided with anaxial bore 5I which is reduced in diameter throughout its mid-portion sothat an upwardly facing valve seat 52 is formed near the upper end ofthe housing and a downwardly facing valve seat 53 is formed nearthe'lower end of the housing. An elongate valve plunger 55, having adiameter smaller than the bore 42 of the tube and larger than thereduced bore 5I of the valve housing, is freely movable longitudinallyof the tube into and out of engagement with the upwardly facing seat 52of the valve housing. The upper end of the valve plunger 55 extendsupwardly through an axial opening 55 in the cover 46 and is providedwith external screw threads at its upper end for receiving an adjustingnut :51 for purposes which will be hereinafter described. A helicalcoiled spring 58 surrounds the valve plunger and is confined between thebottom of the cap 46 and a flange or ring 59 which is riveted orotherwise secured to the valve plunger at a point spaced above thebottom of the cup 40 when the! plunger is in its lowermost position. Thespring exerts its force to constantly urge the valve plunger intoengagement with the upwardly facing seat 52 in the valve housing 50 forcontrolling flow of lubricant from the cup 49 through the tube 4I andinto the reduced passage 5I of the Valve housing.

An elongate substantially L-shaped lift .rod 60, has a bifurcated end 5Ion its short horizontal portion, and the valve plunger 55 extendsupwardly between the arms of the bifurcated end of such lift rod withthe nut 5T above the arms, as clearly shown in Figure 2. The elongatevertical portion of the lift rod extends downwardly through an openingin a guide plate 62 secured by means of bolts 62a to the upper end ofthe housing .45, and then extends on downwardly through an opening inthe table top II. A stop Washer or ring 63 is adjustably mounted on thelift rod above the table top by means of a set screw 64, for limitingdownward movement of the lift rod. A roller wheel 65 is mounted on atransverse pin 66 at the lower end of the lift rod and is positioned tobe engaged by a cam pin 61 carried by a rotatable follower disc 68forming a part of a Geneva movement mechanism. I

` The follower disc 68 is provided with a plurality of uniformly spacednotches 69 in its periphery, and between the notches the periphery ofthe disc is formed with concave sections 10, whereby such concavesections will engage and ride upon the circular surface 1I of theactuating disc 12 of the Geneva type movement. The actuating disc isprovided with an annular flange 413 along one side, and an actuating pin14 is carried by the flange and adapted to engage in the notches 69 ofthe follower disc to cause the follower disc to be turned through apredetermined number of degrees. The circular surface 1I of theactuating disc is cut away adjacent the pin 14 to permit the points oneach side of the notches in the follower disc to pass when the pin isengaged in one of the notches, so that the next adjacent concave surfaceV1I) is turned into contact with the circularsurface 1I of the actuatingdisc. Manifestly, the actuating disc must be turned through a number ofrotations equal to the number of notches 69 in the follower disc tocause a single rotation of the follower disc. l

The actuator disc is mounted on the drive lshaft 15, which actuates theother parts ofthe strip casting machine and more particularly whichdrives the cam or gear mechanism which causes reciprocation of the pushrod I9 to actuate the piston I5 of the molten metal pump. The followerdisc 61 is mounted upon a stub orjack shaft 16 extending parallel to themain drive shaft and spaced therefrom a distance suiicient to permit theco-action of the follower .disc and the actuator disc just describede.

The foregoing constitutes the usual Genevatype movement, and causesintermittent movement of the lift rod 60 when the pin 61 engages theroller wheel 65 at the lower end of such lift rod. It will be seen,therefore, that the lift rod 60 will be lifted by the pin 61 one timefor each six revolutions of the principal drive shaft 15 in the form ofthe movement illustrated in the drawings. Manifestly, the number ofnotches 69 and concave faces 1D formedA on the follower disc 68 may bevaried from the number shown, to obtain different ratios between therevolutions of the principal drive shaft and the lifting of the liftrod. Also, it will readily be seen that any other suitable mechanism forcausing intermittent movementy of the lift rod 60 may be employed ratherthan the Geneva movement illustrated.

When the lift rod 60 is elevated by the pin 61, the bifurcated end 5I ofthe horizontal porthe roller 65 at the lower end of the lift rod, therod will drop downwardly until the stop ring 63 engages the uppersurface of the table top I I of the strip casting machine, and the bi-ffurcated end 6I of the lift rod will be normally spaced slightly belowthe nut 51 on the valve plunger. The valve plunger is normally con'-stantly resiliently held in engagement with the tion of the lift rodwill engage beneath the nut 61 threaded on the upper end of` the valveplunger 55, and will lift the valve plunger away from the upwardlyfacing seat 52 in the valve housing 50. The distance which the plungerwill be lifted may be variedand controlled byV adjusting the position ofthe nut 51.-,on theY threaded upper endof the valve plunger.V :When

upwardly facing valve seat 52 by means of the helical spring 58 actingdownwardly upon the flange member 59 carried by the plunger, so that theoil or any other desired lubricant contained in the cup 40 will beprevented from flowing from the bore 42 of the tube 4I into the reducedpassage 5I of the valve housing until the plunger is lifted by the liftrod in the manner just described. Furthermore, the engagement of thevalve plunger with the seat 52 will also prevent entrance of moltenmetal into the bore of the lubricant tube 4 I.

It is preferable that the movement of the lift rod which elevates thevalve plunger to permit' lubrficant from the reservoir or cup to flowinto the throat passage be so timed with respect to the movement of thepiston I5 of the molten metal pump in the crucible that the valveplunger will be elevated for only a short portion of the time duringwhich the piston is moving upwardly to draw molten metal from thecrucible into the pump cylinder and the molten metal in the throatpassage is under suction. With the valve plunger so elevated to open thepassage through the valve seat, lubricant from the reservoir andlubricant tube 4I may flow past the plunger and seat and into Ythethroat passage.- The amount of lubricant permitted to flow past theplunger and seat is therefore controlled by the'interval of time duringwhich the plunger is lifted off such seat, and lubricant cannot flowfrom the reser' voir into the throat passage at any other time.

For preventing molten metal from the throat passage from backflowingupwardly into the reduced portion 5I of the bore of the valve housing, acheck valve float or closure member 83 is movably mounted in the lowerportion of the valve housing below the downwardly facing seat 53 formedtherein, The check valve float is provided with a conical seatingsurface at its upper end which is arranged to engage against the seat 53to prevent upward flow of molten metal therepast. The check float ismaintained in place in the lower open end of the valve housing by asmall transverse pin 82 fixed across the lower end of the housing andsupporting and limiting downward movement of the float. The pin permitsthe float to move a sufficient distance below the seat 53 to allowlubricant to pass from the reduced portion of the bore of the housinginto the throat housing, but when the molten metal is placed underpressure by the downward movement of the piston of the molten metal pumpthe float will be lifted back into engagement with the downwardly facingseat to prevent the molten metal from flowing into the reduced passageof the valve housing or to the valve plunger 55. Since the check floatis preferably formed of steel cr similar metal, it will float upon themolten type metal and will normally engage against the downwardly facingseat 53. However, when the pump piston is moved upwardly to drawadditional molten metal into, the cylinder a suction is created in thethroat passage which will draw the check float downwardly away from theseat and permit lubricant containedl in the bore of the pin 61 has movedout of engagement vwith 7s the valve housing to be drawn past said floatand aange@ im@ fine breiten' metal in the 'throat passage.

Wheifthepiston-'again 'moves downwardly, presfsiire is Yi'eap'plied toIthe molten metal and the 'check o`a`t lis lifted back into engagementwith 'the 'valve seat 53, v'and the lmolten metal is `thus pievbritedfrom 'entering the 'bore of the housing. 'Any incitan inetal passing thecheck oa't will, fliowev'e'r, be prevnted'from entering Vthe bore of thelubricant tube 41 'by 'the valve plunger 55 enfgagedagain'st theupwardly facing valve se'at 52'. -I-n '`iiect, therefore, the reducedportion 5i of the l-borefof the valve 'housing forms a small secondarylubricant clhamberfseparated from the lubricant reservoir vor cu-'p 40by the engagement of the valve lplunger 55 'with the upwardly facingseat 52 at the upper end of the valve housing, and separated from 'themolten metal in the throat passage bythe check 'float 80 engaging thedownwardly facing seat 53 'at the flower end of the housing.

Therefore, rwhile 'the molten meta'l'in the thi-'oat passage is :underpressure Aapplied by the down;- ward-stroke of the pump piston themolten metal cannot yenter "the lreduced 'passage or secondary cham-ber5|, or if some metal does pass such checkv float the valve plunger 55engaging the seat 52 prevents such metal from entering the boreof thelubricant tube and the reservoir. Furthermore, when the pump piston ismoved upwardly to draw iadditional molten metal into the chamberi ntothe throat passage until the valve .z

plunger 55 is lifted by the lift rod. As has Yalready ybeen pointed out,the valve plunger is not lifted except during a lshort interval of timeduring the upward or suction stroke of the pump piston, so thatthepassage through the upwardly facing seat is open during only a smallpart of the time that the check float is open. Thus, the lubricantpermitted to pass from vthe reservoir through the secondary chamber intothe throat' passa-ge is limited and controlled in amount by the periodof time during which the valve plunger :is elevated. Also, a smallportion of the lubricant will be retained in the secondary chamber 5lwhen the check iloat again seats against thedownwardly facing valveseat, and this lubricantwill pass into the throat passage duringsubsequent opening movements of the check iioat occurring when. thevalve plunger 55 is not lifted. Thereforathe quantity of lubricantadmitted into the molten metal in the throat passage is stricthcontrolled by the valve plunger, and lubricant is not, admitted to thepassage except duringrytheY suction stroke of the molten metal pumppiston.

Due to the fact that the lubricant cup 46 and the lubricant conductortube il a-re supported in the housing i5 by means of the screw-threadedengagement of the enlarged portion vof the tube with the housing, itwill readily be seen that the cup, tubejand valve housing 55 may belifted from within the opening ifi after the scret;v threads -have beendisengaged. Such removal of the lu-bricator provides access to the valvehousing, whereby the seats and check float may be renewed or the housingreplaced, if desired.

From the foregoing, it will be seen that an improved lubricating devicehas been provided for feeding lubricant into the strip forming channelof the die of a strip casting machine for making printers leads, slugs,and rules and the lll 'lile'gfsaid lubricating mechanism havin'giva"Jmeansfior-positively Acontrolling the admi on of lubricant 'to thechannel of the die of the strip forming machine. 'It will further be`seen that valve ans Hof the lubricating mechanism is v ently restrainedin closed position, and is open d only at predetermined intervals 1t'lubricant through the small 4secondary chamber vintothe throat passageof thev machine; Further, they lubricating mechanism has been provided-iri'eans l'for preventing backeiiovv of -fli-ibricant and molten metalinto the body of the `Iubric'a-to'r mechanism. The provision forcontrolled opening of the valve plunger con# trolling vfilo'w o'flubricant from the reservoir; combination with the secondary chamber,provvides for strict control of the amount of lubricant adfiiitted tolthe' throat passage to pass with the `"riiolten fr'netal through thedie channel. It'wili also Abese'en that the valve ymechanism is operatedat intervals which preclude the admission 'of molten meta-l into Ythevalve housing tor lubriicater body; that the opening of the valves'is socontrolled that undesired ow of nuids in either direction is prevented;and, that the lubricator mechanism is readily adjustable and removable,.if desired. A

The foregoing description of the intention is explanatory only, andchanges in the details "of the construction 'ilhistratedmay bemad'e bythose skilled in the art, within the scope of :the appendedfclaims,'without departing from the spi-rit of the invention. i

What I claim and desire to secure by Letters Patent is:

, l. In a strip casting machine having a crucible for containing moltenmetal and having a sage from the crucible to a strip forming die andhaving a molten metal pump for forcing molten metal vfrom the cruciblethrough the passage 'tof the die, aflubricating mechanism forintroducing lubricant into vthe passage from the cruciblel to the diewhich includes, a lubricant reservoircup, a conductor tube from thereservoir 'cup to .the molten metal passage of the machine, upwardly:operable downwardly closable valve `nfiembers 'in the conductorcontrolling o'w of lubricant from' the reservoir to the molten metalpassage,V a spring inthe reservoir cup normally biasing thev valvemembers toward closed position, a lift rod connected with the movablevalve member for lifting said movable valve member against the action ofthe spring, and an intermittent move,- nnt `rnchanism for lifting the`lift rod and operated :in timed relationship with the movement of themolten meta-l pumpI for opening the valvemeans "at predetermined desiredintervals to 'admit lubricant to the molten metal passage,l a vcheckvalve in the conductor tube spaced from the first-named valve membersfor preventing 'of molten metal into said conductor, me

boreY of the 'conductor between said nrstmamed valve members and saidcheck valve constituting a secondary lubricant reservoir.

Alubricatig mechanism for a strip casting machine 'having a melting potwith an outlet passage therefrom to a strip forming die which includes,a lubricant container having a ldowncommunicatir'i'g'v wardly eiitendingconductor therewith, a'valve `housing removably connected nig 'with theoutlet passage from the "melun-g' pet' of the strip casting machinewhereby lubricant from the container may pass through the conductor andvalve housing to the outlet passage, a downwardly movable valve memberin the lubricant conductor engageable with the upwardly facing seat inthe valve housing, a spring in the lubricant container engaging andnormally biasing said valve member to closed position in engagement withsaid upwardly facing seat, and an upwardly movable check Valve member inthe lower portion of the valve housing below the downwardly facing seatengageable with said downwardly facing seat for preventing back flowthrough the valve housing and conductor to the lubricant container.

3... A lubricating mechanism for introducing lubricantl into the passagefrom the crucible to the die o'f 1a strip casting machine whichincludes, a lubricant reservoir cup, a conductor tube from the reservoircup to the molten metal passage of thejmachine, a valve housingremovably. connectegLto the lower end of thefconductor tube and having aflow passage therethrough with an upwardly facing valve seat and aspaced downwardl" Afacing valve seat formed therein; an elongate valveplunger movable vertically in the and biasing the plunger into engagVHARRY "L. HORN.

REFERENCES CITED The following references are of yrecord in the le ofthis patent:

UNITED STATES PATENTS Number Name Date 1,438,951 Elrod Dec. 19, 19221,466,125 Faupel Aug. 28, 1923 1,567,363 Elrod et al. Dec. 29, 19251,800,938 Hedly Apr. 14, 1931 1,913,945 Morris et al. June 13, 1933

